Answer:
x = -1
Explanation:
Solve for x:
3 (2 x - 1) = 7 x + 5 x + 3
Grouping like terms, 7 x + 5 x + 3 = (5 x + 7 x) + 3:
3 (2 x - 1) = (5 x + 7 x) + 3
5 x + 7 x = 12 x:
3 (2 x - 1) = 12 x + 3
Expand out terms of the left hand side:
6 x - 3 = 12 x + 3
Subtract 12 x from both sides:
(6 x - 12 x) - 3 = (12 x - 12 x) + 3
6 x - 12 x = -6 x:
-6 x - 3 = (12 x - 12 x) + 3
12 x - 12 x = 0:
-6 x - 3 = 3
Add 3 to both sides:
(3 - 3) - 6 x = 3 + 3
3 - 3 = 0:
-6 x = 3 + 3
3 + 3 = 6:
-6 x = 6
Divide both sides of -6 x = 6 by -6:
(-6 x)/(-6) = 6/(-6)
(-6)/(-6) = 1:
x = 6/(-6)
The gcd of 6 and -6 is 6, so 6/(-6) = (6×1)/(6 (-1)) = 6/6×1/(-1) = 1/(-1):
x = 1/(-1)
1/(-1) = -1:
Answer: x = -1